Island



3 Sheets-Sheet 1.

J. OLMSTED.

' YQTJMJRUPLEX TELEGRAPH. y Nn.170,963. :Patented Dec.14,1`875.

INVENTOR N. PE'ERS. FHUTO-UTHOGRAPNER. WASHINGTON, D C.

3 Sheets-Sheet 2.

J. OLMSTED.

QUADRUPLEX TELEGRAPH.

- Patented`Dec.14,1875.

No.l'fmeea.

N.PET|:RS, PHOTmLITHOGRAPHEH, WASMNGTON D C 3 Sheets-Sheet 3.

J. OLMSTED. QUADRUPLEX TELEGRAPH. `No.170,963'. Patentednec.`14,1a75.

Fili. l

Ba?. .Zin J70 l,

WITNEssEs NVENTQR2 @#Mh i 'UNITED STATES PATENT OFFICE.

JOSEPH OLMSTED, OF PROVIDENCE, RHODE ISLAND.

IMPROVEMENT IN QUADRUPLEX TELEGRAPHS.

Specification forming part of Letters Patent No. 170,963, dated December14, 1875; application filed November 2, 1875.

To all whom 'it may concern:

Be it known that I, JOSEPH OLMsTED, of the city and county ofProvidence, in the State of Rhode Island, have invented certain new anduseful Improvements in Telegraphic Apparatus; and I do hereby declarethat the fol-` lowing speciiication, taken in connection with thedrawings furnished and forming a part thereof', is a clear, true, andcomplete description of' my invention and an apparatus embodying thesame.

I seek by my invention the simultaneous transmission, on a single wire,of four signals, two in each direction. This requirement, as met by me,necessarily involves a capacity for transmitting two signals at the sametime on the same wire, whether one signal be transmitted from each end,or both be transmitted from the same end of the wire.

It has heretofore been proposed, by means of so-called quadruplextelegraphic apparatus, to simultaneously transmit two signals ormessages over the same wire, in the same direction, by employing thepositive and negative currents alternately; also, it has been heretoforeproposed to send two signals or messages simultaneously from oppositeends of a line by employing both the positive and negative currentsalternately.

By means of my invention I am enabled to accomplish these results byemploying a bate tery-current which is applied to the line in the usualmanner, and without alternation of current as heretofore proposed.

For accomplishing my purpose I employ the following well-known means:the linewire, two main batteries, two ground-connections, fourlinger-keys, four sounders, several resistance-coils or rheostats, twotransmitters of' ordinary construction performing their proper function,two cut-outs or shuntswhich resemble transmitters of ordinaryconstruction, for performing an automatic controlling iniiuence over theelectric currentsix relay-magnets, and several local batteries.

In addition to the above I employ two transmitters, each having anarmature-lever of novel construction, in that it is composed of twoplates or bars, insulated from each other, and so arranged that each barmay communicate wit-h one of the two usual contact points or stops.These transmitters perform usual functions, and also serve asintermediate circuits for avoiding a resistance-coil when occasionrequires full force of the current.

With the means described, by reason of their novel combination andarrangement with relation to each other, and a novel system of electricconnections, I am enabled to practically attain the object sought, aspreviously indicated.

The line-wire, lnain batteries, and groundconnections are arranged asheretofore. The lngerkeys have local batteries, which are connectedthereto and with the transmitters;

land the sounders have also local batteries connected with them 1n theusual manner;-

but the Sounders are connected with their relays in a novel manner.Adjacent to each ground-connection is a resistance-coil, as heretoforeemployed, for balancing the resistance of the line. Iemploy, inconnection with each of the transmitters, at each end of the line, aresistance-coil, so arranged that either or both of' the coils may beautomatically brought into service when required. The relay-magnets arelocated, as is usual in duplex telegraphic systems, with relation to themain line, the sounders and transmitters, and, as heretofore, theoutgoing current passes through both coils of each relay-magnet at thetransmitting end of the line. Each end of the line is provided withthree relay-magnets. Their armatures are variably weighted. Two of themagnets-one at each endhave their armatures so set that, with a smallportion of the electric current applied to them, their armature-leverswill be held to the front stops, and when this current is lessened thearmature-levers move to the back stops and make connection with theirrespective Sounders. At each end of the line is one of two otherrelay-magnets, each of' which communicates with a sounder. The normal orusual position of their armature-levers is against the front stops, andthey are so weighted that they will remain against said stops until theholdingforce of' the magnets is reduced to about onehalt' of theirnormal power, at which time their armature-levers fall to the back stopsand make connection with their respective Sounders.

Between these two relay-magnets, at each end of the line, I employ stillanother relaymagnet, which is electrically connected by conductors toeach of its neighboring relays. It may have no sounder of its own, butcan be arranged to affect or control the sounder ofthe relay-magnetfirst described, by co-operatin g with or through said relay undercircumstances hereafter recited; or it may be arranged to communicatedirectly with that sounder without co-operating with or through therelay last referred to.

My invention involves a novel method of transmitting two signals at thesame time i over the same line from each end, and in each direction,which consists in placing the battery-current under the control of fourfingerkeys without changing the relations between the poles of thebatteries and the line-wire, so that it may be wholly cut off from theline under 011e condition, or reduced to, say, twothirds ofits powerunder another condition, and to, say, one-third of its power underanother condition, or employed in its full force under still otherconditions.

' My invention consists mainly in the combination, with four keys, foursounders, a line- Wire, suitable main and local batteries, and suitableintermediate conductors, of means for directing the battery force orpower to the main line in three unequal powers; means for whollyneutralizing said power; and of means for placing' each sounder intocommunication with its key, whereby, with unchanged relations betweenthe poles of the main batteries and the line-wire, messages or signalsmay be transmitted from two of the keys at the same time over the samewire and in the same direction, while signals are being received fromboth of the other keys, as set forth.

My invention also consists partially in the combination, with theline-wire and its batteries, of two keys and their local batteries, twotransmitters, controlled by the keys and their batteries, tworheosta-ts, or equivalent means,

for graduating the power of the battery-current to line, controlled bythe transmitters, a'

Y cut-outor shunt allat one-end of the line, and

at the other endvof the line three relay-magnets with armaturesvariously weighted, and two sounders with local batteries controlled bysaid relay-magnets.

It further consists in the combination of two keys and their localbatteries with a transmitter capable of A'performin g usual service, atransmitter having an armature-lever composed of insulated bars orplates, two rheostats, and a system of connecting-conductors, wherebyadesired portion of the' battery-current Vmay be withheld, or thecurrent cut off entirely. Y

It further consists in the combination, with a ground-wire and itsrheostat, of an automatic shunt or cut-out, composed of anelectromagnet, an armature, and the usual back and front stops, abattery-wire, which charges the magnet, a conductor, which connects thefront stop and armature with the ground-wire on each side of itsrheostat,-and a means for cuting oli' the current from the battery tothe magnet ot' the cut-out.

lt further consists in the combination, with a sounder and its localbattery, of two relaymagnets, having' their armatures set at differentresistances, and arranged to separately operate the sounder when call ismade thereon from its proper transmitting-key.

It further consists in the combination of a sounder having a localbattery and a relaymagnet, which normally holds its armature lever tothe front stop with but little electro-- magnetic force, and permits thesounder to operate when its armature-lever is on its back stop with asecond relay-magnet, which is coni nected to the rst, holds its ownarmature-lever to itsfront stop by a greater force, is located betweenthe iirst relay and the line-wire which charges the magnets of bothrelays, and is arranged to shunt the current received by it to aground-wire, and so protect thel weaker magnet, in the performance ofits duty, from a current which would prevent it from causing its sounderto respond to its proper key.

And still further my invention consists, in a transmitter, of thecombination, with an electro-magnet, of an armature-lever, composed oftwo separate bars or plates, insulated' from each other, and arranged sothat a surface of one plate will communicate with the front stop, and asurface of the other plate or bar will communicate with the back stop,whereby each bar or plate may serve as a conductor independently of theother.

InV order to Vfully describe my invention, I will refer to theaccompanying three sheets of drawings, in which- Figure l, Sheet .1,illustrates a complete apparatus at the home station; and Fig. 2, Sheet1, a similar apparatus at the Aforeign station. Fig. 3, Sheet 2,illustrates a single apparatus, whereby two signals may be sentsimultaneously over the same line in the same direction.'

It will be seen that Fig. 3 is a counterpart ofone-half of eachapparatus shown at each end of the wire in Figs. 1 and 2, and theseveral parts of the apparatus are lettered as in those figures.

Figs-5 and 6, Sheet 3, illustrate different modes of batteryarrangement. t

The main-line -wire between the two stations is indicated at V.

A and B denote the linger-keys at the home station, Fig. l, and C and Dthe keys at the foreign station, Figs. 2 and 3. The sounders of the homestation are shown at E and F, and at G and H at the foreign station.Each linger-key and sounder is provided with a local battery, as at u.-The linger-keys are in each instance connected with the magnets of theirrespective transmitters, which are shown at I and J in the home station,and K and L in the foreign station. Their connecting-conductors areshown in dotted lines in each in-v in anwstance, and they are arrangedin the usual manner. The souiiders are also connected with theirrespective relay-magnets by conductors, indicated by dotted lines, asfollows: Home sounder E to relay O, sounder F to relay Q, and at theforeign station sounder Gr may be connected in like manner, as shown inFig. l, to relay R, or by a different mode of connection, hereafterfully described. Sounder H is, however, connected with its relay T inthe same manner as -shown at the home station. The relay-magnets at thehome station have their counterparts at the foreign station. The mainbatteries are plainly designated in the drawings, and theground-connections are shown at Z.

For the purpose of illustration it will be assumed that 150 representsthe full power of the main battery; and it is to be understood that thethree relay-magnets at each end of the line have armatures, which arevariably weighted, but that they correspond in this respect with therelays at the other station, as follows: relay O with R, P with S, and Qwith T. The armatures of relays marked 150 are attracted by that power.Those of relays marked are released at that or a lesser power. Those ofrelays marked zero (0) are released when their magnets are powerless.

I will first describe the normal condition of the linel when at rest.Although the full force ofthe battery is represented by 150 the normalcondition of the entire apparatus is 100, at which ti mev thearmature-levers of the trans mitters I J and K L are, of course, ontheir back stops, their magnets not being then affected by the fingerkeylocal batteries. The armature-levers of the cnt-outs or shunts M and N,and the relays 0, Q, R, and T are all against their front stops. Thearmatures of relays O and It are so set that when the power of thebattery is reduced to zero they will be released from their front stops,while the armatures of relays Q and T are so set that they will bereleased from their front stops when the battery-force is not greaterthan 50. The armatures of the relays P and S are so weighted that theyremain on their back stops, unless the power of their magnets isaugmented to a force nearly or quite equal to 150, or the full force ofthe battery, which is, when the line is at rest, modified to 100, asstated. This modification ofthe power of the battery is effected asfollows, in connection with Fig. I: the current from the main battery,at the home station, for instance, by way of the wire indicated in solidlines at b, on reaching the transmitter at I finds a fork or branch inits conductor. One ofthese branches is obstructed by the resistance-coilshown at No. l, and therefore the current passes along the armature a oftransmitter I through its back stop; thence, by another wire, (indicatedin solid line's and by arrows Nos. I and 2,) to and through theresistance-coil No. 2, which partially neutralizes the power of thecurrent to the extent of one-third of its full capacity,

leaving a force, which, as before stated, may be represented by 100. Atthe foreign statioii the same arrangement of conductors andresistance-coils is shown. The main -battery current reaches the mainline V by passing through the magnet of the 'cut-outor shunt M at thehome station, and through each core of each magnet of the relays 0,1),and Q, and at the foreign station by passing through magnets of cut-ontN and relays R S T, as is clearly shown in each case by conductorsindicated in solid lines.

For explaining the working of the apparatus I will first describe how asingle message may besent over the line from the foreign to the' homestation. As before stated, Fig. 3, Sheet 2, illustrates a singleapparatus, and its parts are designated by the same letters employed inFigs. 1 and 2. In said Fig. 3 the transmittin g devices are as in Fig.2, and the receiving devices as in Fig. 1, and therefore either of thetwo sheets of drawings may be referred to in connection with thedescriptive matter relating to the transmission of signals from theforeign to the home station.

The finger-key at G is depressed, which permits its local battery u. tocharge the magnet of transmitter K, which attracts the armature a to thefront stop. The current from the main battery, having now no conductorexcept the wire shown in solid line, passes, in direction of arrow No.3, to resistance-coil or rheo stat No.3, whereby the force of thecurrent is reduced from 100 to 50; beyond this po nt it continues on thewire b to transmitter L, as next described. This transmitter L has anarmaturelever, a', of novel construction. (I1- lustrated more fully inFig. 4, Sheet 2.) It is composed of two bars or plates, which areinsulated from each other. One bar, as at w, constitutes the frontsurface of the armaturelever, for contact with the front stop. The otherbar, as at y, constitutes the rear surface, for contact with the rearstop. The current from the rheostat No. 3, thereby reduced to 50, passesto the upper portion of the armaturelever a; thence to the back stop;thence by wire, as per arrow No. 2, to the rheostat No. 4; thence. toand through the magnet of shunt or cut-out N, as indicated by arrow 5,to a point where the conductor is divided into two parts, each partconnecting with one of the coils of the magnet of relay It, passingthrough said coils, and thence through the coils of in agnets in relaysS and T in like manner. One portion of the current, after passing relayT, passes to the ground-wire, as per arrow 6, and the other portion tothe line-wire V, as per arrow No. 7. As is well known, the dividedcurrent, in thus passing through each coil, fails to affect thesemagnets in any manner.

It will be nremembered that the arma-turelever of relay Q is against itsfrontstop, and it is here to be noted that the release of this armatureand its contact with its back stop permits the sounder F to be operatedby its local battery. The armature-lever of relay Q is held to thefront'stop by a force greater than 50; and as the power of the currentfrom key G is but 50, the armature is therefore released and the sounderF operated.

Leaving the key C down, and the sounder F executing its signal, I willnext describe home station: The key D being depressed, the magnet oftransmitter L is charged, and its armature-lever a carried to its frontstop. The battery-current, being already reduced to 50,

1s still'further reduced to z ero by cutting off armature of relay O isreleased from its front stop, and, by contact with its back stop,permits the sounder E to be operated by its local battery.

Havingdescribed how keys G and D may simultaneously operate theirrespectivesounders, I will now show how key D may continue to controlits sounder after key C has ceased control of sounderF: Pressure beingremoved from key G, the magnet of transmitter K releases its armature,which returns to its back stop. They battery-current then, instead ofpassing through rheostat 3, passes along armature-lever a of transmitterK, through its back stop, along the conductor to the back stop oftransmitter L, thence toward the rheostat 4; but finding resistancethere, it takes the easier conductor, as indicated by arrow N o. 8,backward and downward to the under plate of the armature-lever a oftransmitter L thence, as before, to the main wire, with the full forceof the battery-z. e., 150. On reaching the relay P at the home station,the entire current is shunted thereby to the ground-wire, leaving therelay 0 still under control of the key D. The full battery-currentapproaches the relay P, as indicated by arrow N o. 9, and is shuntedmagnet, and from thence, as per arrow No.10, by wire (in dotted lines)back to the front stop of the relay; thence along its armature-lever toits base; thence by the wire (in dotted lines) to opposite end of theother coil, as per arrow No. 1l, back through the coil to its front end;thence to the ground-wire, as 4per arrows l2 and 13.

It will be seen that the outgoing current from the home station in nomanner affects the home relays and sounders, because the one division ofthe current ultimately reaching the line-Wire, and the other portion theground wire.

Signals from keys A and B, at the home station, will be transmitted tothe sounders at ',he foreign station, in the same manner as has )eendescribed in connection with signals from he opposite direction. Thelocal-battery coniections between relay 0 and its sounder E, ,t the homestation, are shown to be somerhat unlike the connections between therelay R and its sounder G at the foreign station, and it will be seenthat the relay S is also connected with the sounder G. In order toexplain this latter mode `of connection, it will be assumed that asignal is being transmitted from key B of home station to sounder G ofthe foreign station. On depressing the key B, the magnet of transmitterJ places its armature-lever@ on its front stop, the battery-eurrentalong wire, as at arrow N o. l, reaches the back stop of relay J, thenceproceeds upward, and, Iinding resistance at rheostat N o. 2, goes in theopposite direction therefrom, as indicated by arrow 14, to the lowersurface or bar of armature-lever a', thence to the front stop, andbeyond, as indicated by arrow No. 15, and so on, as before described,one portion of the current going to the main wire, and the other toground. On reaching the foreign station, the force of the current being150, (rheostats Nos. l and 2 being both cut out,) it passes throughrelay T, and, acting on relay S, places its armature on the front stop.The sounder G and its local battery are connected, as by wire shown indotted lines, to the front stop of relay S, and also to itsarmature-lever, and when the armature is thus brought forward it permitsthe sounder G to operate. If, while key B was closed, key A should alsobe closed, the current being thereby cut off entirely, the relayS will,of course, release its armature, but simultaneouslythe relay R will alsorelease its armature to the back stop, and thus the control of sounder Gis transferred from relay S to relay R. The cut-outs or shunts M and Nare of service only when it is desirable that the ground -rheostats Nos.5 and 6 be wholly out out. When relays O and R are operated, as hasbefore been stated, the batteryforce has been reduced to zero, at whichtime the magnets of the cut-outs or shunts M and N release theirarmatures, which pass to their back stops, and, through their levers,communication is opened, by wire shown in dotted lines, from ground-wireto ground-wire, on opposite sides of the ground-rheostats 5 and 6. Whenoperating two keys and transmitting two messages over the line in thesame direction, the messages may both be dropped at any number ofintermediate stations, if these latter are provided wit-h sounders andrelays of the general character of those herein described.

It will be seen that the rheostats l, 2, 3, and 4 serve only as meansfor dividing the power of the battery into requisite divisions or parts.It will also be seen that for service, under 011e condition, l reducethe power of the battery with reference to the main line to zero. Underanother condition I reduce it to 50, under another' condition to 100,and under still another I employ the full force of the battery, z'. e.,150. Now, I am well aware that ifa battery of twelve cups has a power of150, that eight cups will have a power of 100, and four cups a power of50, and therefore I well know that by the employment of ka battery of,say,

that number of cups, and an arrangement ot' shunts or switches, whichwill be` readily suggested to persons skilled in the art, they may beconnected with transmitters in such amanner, that the battery-force toline-wire may be varied to the same extent, and in substantially likemanner, as herein shown to be accomplished by rheostats Nos. l, 2, 3,and 4.

For the purpose of showing that the rhcostats which, in connection withthe transmitters, serve as means for reducing the power of the batteryto line, may be dispened with, by

employing', say, a-battery divided into three` divisions, each having apower of 50, which, when properly connected, will transmit 150, 100, or50 to line, or be capable of being wholly cut off when a zero of poweris required, I will now describe the form and arrangement of apparatusshown on Sheet 3, Figs. 5 and 6. I will rst refer to the transmittingapparatus shown in Fig. 5.

The keys are shown at'A1 and B1, each with local battery a. Key A1 isconnected to transmitter I1, and key B1 to transmitter J1, as beforedescribed. The battery is in three divisions, which are plainlydesignated in the drawings, and are respectively numbered 1, 2, and 3.These divisions are so connected with each other that, when two or threeof them are employed, they act as one battery in every respect. rIhetransmitters I1 and J1 have armature-levers, which are provided in eachi11- stance with a plug, as at c, composed of good insulating material.Each plug has a wedgeshaped face, and a small metal plate therein, whichis connected to a wire which extends through the plug longitudinally.Opposite each plug is a pair of union springs, as at d and d', whichserve as electric connections for the wires attached thereto. When theplugs c en ter between these springs they are forced apart, breakingtheir direct connection, and each communicates with a metal plate andone of the wires. The back stops of transmitters I1 and J1 are connectedby wire e.

When the apparatus is inthe condition as shown in the drawings, two ofthe divisions oi" the battery, Nos. 1 and 2, are in connection with themain line, which, when the apparatus is at rest, may be represented as100. The battery-divisions connect as follows: Division No. 1, by way ofwire clearly shown, to one side of union spring d; thence through plugin armature-lever'of transmitter I1 to division No. 2, with which itproperly connects; and from the other end of this battery No. 2continues by wire back through the plug and the opposite side of unionspring d along wiref to union spring d1; thence back by wire gto rearend of the armature-lever of I1, thence to its back stop, to the backstop of armature of J1 by wire e, and thence to line with power of 100,received through the proper connection of two batteries, each havingpower of 50. N ow, it is to be remembered, in connection with thel formof apparatus previously described, that we require at the transmittingend of the line the following conditions: Normally, battery-power toline, 100; when key A1 is operating separately We require power to lineof 5U; when key B1 is operating separately we require power 150, andthat, when both keys are operated simultaneously, we require zero. Now,it is to be understood that one of the cut-outs or shunts M or N ot' theprevious figures is to be also employed with the transmitters l1 and J1of this figure, and in precisely the same connection, and that, at theother end of the line c', either set of the relays previously shown maybe connected thereto.

I will first show how a signal may be transmitted from key A1 to asounder like F through a relay like Q of the previously-describedapparatus. To do this the power on the line must be reduced to 50. KeyA1 being depressed the armature-lever of I1 is carried to its frontstop. The withdrawal of the plug c from union springd takes division No.2 of the battery from the line. The two sides of spring cl being in contact maintain connection of division No. 1 of the battery with mainline, and therefore the proper relay at the other end of the line willrelease its armature, and so operate' the sounder. The current, underthese circumstances, passes from division No.1 of the battery to unionspring d, crosses to wircf, thence to wire g. Having no outlet atarmature-lever of transmitter I1, (it being on front stop,) the currentpasses from wire g by way of wire h, to rear end of armature-lever ot'transmitter J1, thence through its back stop to line wire.

I will next show how a signal may be sent from key B1 to a sounder likeE, through relays like O and P of previous figures. It has already beenexplained that either zero or 150 will operate that sounder. Key B1being depressed causes armature-lever of transmitter J1 to move to itsfront stop, and in doing so its wedge-block c separates union spring d',and brings division N o. 3 ot' the battery into connection with wiresfand g, so that the full current from the two divisions Nos. l and 2 ofthe battery joins with that of division No. 3, and, tnus augmented,passes backward on wire g to rear end ot' armature-lever ot' transmitterI1, thence through its back stop by wire c to back stop of transmitterJ1, thence to linewire V with a power of 150.

I will next explain how signals may be tra-nsmitted simultaneously fromboth keys to their respective Sounders. It has already been described,in connection with previous figures, that Sounders E and F may both beoperated simultaneously, because sounder E is operated through anarmature in arelay, which releases it when at zero, and sounder F isoperated by a relay which releases its armature at 50, andv this latterrelay will, therefore, of course perform in the same manner at zero.

It will be seen that, when the armature-lever of transmitter I1 is onits front stop, the division No. 2 of the battery is cutout entirely.The current from division 1 proceeds through union spring d to unionspring d per wire f. The armature-lever of transmitter J 1 being' down,the current passes on the Wire through the plug to division 3 of thebattery, and, joining with its current,- passes through the oppositeside of the plug to opposite sidev of spring'd; thence by wire g to rearend of armature-lever of transmitter l1, which, being down, has noconnection with its back stop, wire e, and line-wire, and, therefore, itcompletely cuts ot'f the divisions Nos. l and 3 of the battery, No.Zzibeing already cut off, and the condition of the line-wire is reducedto zero,

and the two sounders respond. VVhileboth` keys are being thussimultaneously operated, if key A1 be alone released, the armature-leverof l1 falls to its back stop, which puts di-v vision 2 of the batteryinto connection with the current from divisions 1 and 3 by wiresf and gto rear end of armature-lever of transmitter I1, thence' through itsback stop, and via wire e to back stop of transmitter J1, the-nce toline at 150.

If, on the other hand, key Bl be alone released, armature-lever of J 1falls to its back stop, cutting out division 3 of the battery. Thearmature-lever of II being on its front stop, division No. 2 is also cutout, leaving division No. 1 in connection with the lille at a power of50.

rIhere are numerous other modes of affecting the direction of the forceofthe battery to line in three unequal powers, which may be employedwith still other means for wholly cutting them off from the line, one ofwhich is shown in Fig. 6, Sheet 3.

As in Figf, the battery is divided into three divisions, Nos. 1, 2, and3. Neither of these divisions is short-circuited. When at rest division1 sends its current to rear end of lower insulated portion ofarmature-lever of transmitter I2, thence by Wire i through division 2.of battery; thence by wire 7c to back stop through end of the upperinsulated portion of armature-lever of transmitter I2; thence bycoil-wire Z to wire m; thence to rear end of armature-lever oftransmitter J2, along it and through its back stop to line with power ofboth divisions of battery-fi. e., 100.

' When, through key A2 armature of I2 is depressed, it cuts out division2 of battery, and power of division 1 passes through front stop to wirem,- thence, as before, with a power of 50.

, When, through key B2 armature of J 2 is depressed, its lever isbrought -into contact with its front stop, carrying power from divisions1 and 2 through division 3 of battery by Way of wires aand 0 to linewith power of 150.

When both keys actuate simultaneously the armatures of both transmittersto their front stops, division 2 is cut out, and divisions 1 and 3, withpower of 100, proceeds to switch W, where it is cut off entirely,reducing the battery-power to line to Zero. 'This switch W i may becomposed, as shown, of two magnets,

which operate on one armature-lever. Neithermagnet' alone will actuateit, but both will do so, and so cut o the line entirely. These magnetsare, respectively, connected with one of the keys and its usual localbattery, and, therefore, when both keys are depressed, the switch isopened, but neither key separately can affect it.

If, following the depression of the armatures of both transmitters, thatof I2 be released by release 'of key A2, there is an accompanyingclosure of switch W, and the full power of all the divisions of thebattery goes to line at 150.

`With the switch W, constructed as shown, it may be also arranged bymeans of wires p and g, to perform the function of a shunt or cut out,for avoiding a ground-resistance, as shown in Figs. 1, 2, and 3, at Mand N.

It will be seen that when the three divisions of the battery areemployed, as shown in Figs. 5 and 6, they are so connected as to operateas one battery, and therefore yield the requisite intensity or workingforce; also whether I use an undivided battery' with a power of 150,with rheostats-for reducing that power to 100 and to 50, as previouslyshown, or a divided battery ot' three divisions, as shown in Figs. 5 and6, it ,will be seen that I employ for transmitting my simultaneoussignals from one end of the line-wire in the same direction the samecombination of elements, to wit: the keys, sounders, line-wire, main andlocal batteries, and suitable intermediate conductors; means fordirecting the battery force or power to the main line in three unequalpowers; means for wholly neutralizing said force with relation to themain line, and means for placing each sounder into communication withits proper key; and it will also be seen that the relations of .thepoles of the batteries to the main line in both modes of working alwaysremain unchanged.

Although I have thus shown three modes of arrangement for transmittingthe power of the battery to line in three unequal powers, and am awarethat still other similar arrangements may be employed, I prefer the modeillustrated in Figs. 1, 2, and 3, involving the use of the undividedbattery and the rheostats.

It is also to be distinctly understood that I do not limit the mainfeatures of my invention to keys, rheostats, transmitters, cut-outs,relays,"and sounders of any precise construction, as I am well awarethat they may be considerably varied in that respect, and still performthe functions of those employed by me for the purpose of illustrating myinvention.

Having thus described my invention, I claim as newto be secured by theseLetters Patent- 1. The combination, substantially as described, withfour keys, four sounders, a linewire, suitable main and local batteries,and suitable intermediate conductors, of means for separately directingthe battery-force to the line-wire in three separate and unequal powers;means, substantially as described, for

Wholly neutralizing said force; and of means, substantially asdescribed, for placing each sounder into communication with its key,whereby, with unchanged relations between the poles ot the mainbatteries and the linewire, messages or signals may be transmitted fromtwo of the keys at the same time, over the same Wire and in the samedirection, while signals are being received from both of the other keys,as set forth.

2. rI he combination, with the line-Wire, its batteries, suitableconductors, two keys and their batteries, two transmitters, tworheostats controlled by the transmitters, and a cut-out or shunt, ot'three relays with armatures variously Weighted, and two Sounders withlocal batteries, substantially as described.

3. The combination of two keys and their local batteries with atransmitter capable of performing the usual service, a transmitterhaving an armature-lever composed of insulated bars or plates, tworheostats, and a system of connecting conductors, substantially asdescribed, whereby a desired portion of the battery-current may bewithheld or sent beyond the transmitters, or the entire current cutoft'.

4. The combination, with a ground wire and its rheostat, of an automaticshunt or cut-out composed of an electro-magnet, an armaturelever, andthe usual back and front stops, a battery-wire which charges the magnet,aconductor which connects the armature, and one of its stops to theground-wire on opposite sides of itsrheostat, and a means for cuttingott' the current from the battery to the magnet of the shunt,substantially as described.

5. The combination, with a sounder and its local battery, of tworelay-magnets, with armatures varably weighted and arranged toseparately operate the sounder when call is made thereon from its propertransmitting-key, substantially as described.

6. The combination, with a sounder having a local battery, and a relaywhich .normally holds its armature-lever to its front stop with butlittle magnetic power and operates the sounder from its back stop, of asecond relay which is electrically connected to the iirst, holds itsarmature to its front stop With a greater force, is located between therst relay and the limewire, which charges the magnets of both relays,and is arranged to shunt the current received by it to the groundwire,substantially as described, wherebythe weaker relay may be protected inthe performance of its duty when its sounder is called to respond to itsproper key.

7. In a transmitter, the combination, with an electro-magnet and theusual front and back stops, of an armature-lever composed of twoseparate bars or plates insulated from each other, and constituting twodistinct surfaces for engagingI with the stops, substantially asdescribed, whereby each bar or plate ofthe armature may serve as anindependent conductor, as set forth.

JOSEPH OLMSTED.

Witnesses:

WM. C. Woon, PHILIP F. LARNER.

